Our research uses neuroimaging to investigate the brain's reward circuitry and its response to food stimuli with the aim of better understanding human eating behavior and susceptibility to obesity. We found that the dopamine binding potential in the dorsolateral striatum is positively related to opportunistic eating behavior and obesity. Some researchers have speculated that dopamine binding is nonlinearly related to adiposity and we are now planning future studies to clarify the role of dopmanine signaling in obesity.